Release mechanism for large chain

ABSTRACT

A release mechanism for use with relatively large chain, such as mooring chain of ships, drilling platforms and the like is disclosed which comprises an elongated cylindrical body having link portions integrally formed at opposite ends for connection to the chain. The body of the mechanism has two disconnectable sections, each of which have a generally radially directed flange adjacent a circumferential line of disconnection. A number of locking shoes bridge the line of disconnection, and each of them have a pair of generally opposed radial surfaces for engaging the flanges to hold the two sections together. One end of each of the shoes has a rocker portion that curves radially inwardly relative to the side wall. A concentric cam holds all of the locking shoes against the outer wall of the body sections and holds the sections together. Activation of internal electrical and hydraulic portions of the mechanism produces axial movement of the cam which contacts the rocker portion of the shoes and causes the shoes to disengage the flanges and permit the sections of the body to disconnect.

XR 3,905,190 SR UIHLCU tat-ales ratent r 91 Pearlman 1 Sept. 16, 1975 1 RELEASE MECHANISM FOR LARGE CHAIN [76] Inventor: Michael D. Pearlman, 2342 Euclid Ave., El Cajon, Calif. 92021 [22] Filed: Oct. 30, 1974 [21] Appl. No.: 519,345

[52] U.S. Cl. 59/93; 114/230; 114/235 A;

Primary Examiner c. W. Lanham Assistant Examiner-Gene l. Crosby Attorney, Agent, or Firm-Fitch, Even, Tabin &

Luedeka [57] ABSTRACT A release mechanism for use with relatively large chain, such as mooring chain of ships, drilling platforms and the like is disclosed which comprises an elongated cylindrical body having link portions integrally formed at opposite ends for connection to the chain. The body of the mechanism has two disconnectable sections, each of which have a generally radially directed flange adjacent a circumferential line of disconnection. A number of locking shoes bridge the line of disconnection, and each of them have a pair of generally opposed radial surfaces for engaging the flanges to hold the two sections together. One end of each of the shoes has a rocker portion that curves radially inwardly relative to the side wall. A concentric cam holds all of the locking shoes against the outer.

wall of the body sectionsand holds the sections together. Activation of internal electrical and hydraulic portions of the mechanism produces axial movement of the cam which contacts the rocker portion of the shoes and causes the shoes to disengage the flanges and permit the sections of the body to disconnect.

18 Claims, 6 Drawing Figures RELEASE MECHANISM FOR LARGE CHAIN The present invention generally relates to automatic release mechanisms and, more particularly, to automatic release mechanisms for large chain or the like that are adapted for remote control actuation.

Relatively large mooring chains that are used for mooring large ships, drilling platforms vessels and the like that are moored or anchored at sea occasionally 1 must be severed while under high load.

" In the past, mooring chains have been severed by cutting them or have merely been run out by a winch. While these ways are effective for most circumstances, there is a limit in the length of chain that can be run out, and the cutting of chain can take quite some time because the chain is quite large, i.e., the thickness of the metal in the links can be three inches or more.

Accordingly, it is an object of the present invention to provide a remotely controllable release mechanism that is operable underwater to release or separate large chain while under high load.

Other objects and advantages will become apparent upon reading the following detailed description and while referring to the attached drawings, in which:

FIG. I is a plan view of the release mechanism embodying the present invention;

FIG. 2 is an end view of the mechanism shown in FIG. 1;

FIG. 3 is an enlarged plan view of the mechanism shown in FIG. 1 with portions removed to reveal the internal structure thereof and shown in its locked or armed configuration;

FIG. 4 is a view similar to FIG. 3, and illLsLatin mechanism immediately after actuation;

FIG. 5 is a cross section taken generally along the line 5-5 in FIG. 3; and,

FIG. 6 is a schematic diagram of the general hydraulic circuit utilized in the mechanism of the present invention.

Turning to the drawings and particularly FIG. 1, there is shown a release mechanism, indicated generally at 10, in conjunction with a large mooring chain 12 which is shown in phantom.

Broadly stated, the release mechanism comprises 2 bodysections l4 and 16 which are separable or disconnectable along a line indicated at 18. When the mechanism is activated, the sections 14 and 16 can separate from one another to relieve any load or tension that is placed upon the mechanism 10 and chain 12. Thus, in the event a drilling platform, ship or the like must be released from anchor, because of unusually foul weather, or other dangerous conditions such as, for example, the approach of an iceberg on a collision course with an anchored platform which necessitates a quick release of the anchor chain, the release mechanism 10- can be activated by predetermined coded accoustic command signals, the receipt of which initiates a series of events which result in the body sections 14 and 16 being separated from one another to release the platform or the like which is anchored by the chain 12.

-Attached to the end of each of the body sections 14 and 16 are integrally formed link portions 20, each of which have an opening 22 .so that an anchor shackle or link can be connected to the chain 12. Upon separation of the body elements 14 and 16 along the disconnect line 18, the separated sections will be attached to the respective links of chain to which they are attached and can thereafter be retrieved andreconnected at a later time. In keeping with the present invention, it should be understood from the plan and end views of FIGS. 1 and 2 that the release mechanism 10 of the present invention is compact and streamlined and has no outwardly protruding components that would interfere with its operation and deployment. Moreover, as will be more comprehensively described hereinafter, the hydraulic, electrical and movable structural elements that operate to release the mechanism are contained within the outer side walls of the cylindrically shaped mechanism and are therefore protected from physical abuse as well as the corrosive underwater environment in which the mechanism is intended to operate.

Each of the body sections 14 and 16, together with their respective link portions 20 are preferably integrally formed as unitary elements so that maximum strength is achieved. In this regard, the side walls of the body sections 14 and 16 may be several inches thick, and the mechanism 10 may approach 8 feet in overall length and may have a weight of about 6500 pounds so that it can achieve design breaking loads of up to a million pounds, for example. It should be understood that several chains and release mechanisms 10 with working loads of 300,000 pounds, for example, may be used to moor or anchor drilling platforms and other massive structures that may be used at sea. Since the body sections 14 and 16 are preferably of unitary construction with the outer side walls providing the primary tension or load-bearing capability, a number of access plates 24, suitably attached by bolts 26, are provided to permit maintenance and the like of the internal components of the mechanism. The plates preferably have gaskets (not shown) provided to make a watertight seal.

To actuate the mechanism 10 and cause the release or separation of the body portions 14 and 16 from one another along the disconnect line 18, and referring to the enlarged plan view of FIG. 3, the body portion 16 has a watertight control compartment, indicated generally at 30, which houses electrical modules 32, hydraulic accumulators 34, hydraulic valving 36 and a hydraulic cylinder 38 and piston 40. The electrical modules 32 include a receiver which is adapted to receive, amplify and decode an accoustic release command signal that is sent from a command transmitter. The receiver is operably connected to the hydraulic accumulators and valve components of the mechanism so that the piston can be driven to cause the release of the mechanism in response to a release command signal being accoustically transmitted from a control station. It should be understood that the electrical and hydraulic components in the control compartment 30 are shown in schematic and idealized form.

Turning now to an important aspect of the present invention and referring to FIGS. 3 and 4 which illustrate the mechanism in its locked and released states respectively, it is seen that the side wall of each of the sections 14 and 16 is substantially increased in thickness immediately adjacent the line of disconnection 18. More specifically, the side walls of the sections 14 and 16 have an inwardly directed annular flanges 42 and 44, respectively, each'of which have respective angled surfaces 4-6 and 48. At the line of disconnection 18, the flange 44 has an annular tongue 50 that seats within a cooperatively configured groove 52 in the flange 42.

Thus, when two body sections 14 and 16 are coupled together, the tongue and groove prohibit any transverse movement between the two sections.

To hold the two body sections 14 and 16 together, a number of locking shoes, indicated generally at 56, are provided, with the locking shoes 56 extending generally around the inside of the side walls of both the body sec-' tions 14 and 16 adjacent the line of disconnection. It should be understood that while only two of such locking shoes are shown in FIGS. 3 and 4 for the purpose of clarity of illustration, there are additional locking shoes utilized, such as shown in the cross section of FIG. wherein eight locking shoes are illustrated. While the number of locking shoes in and of itself is not critical there should be a sufficient number so that extraordinary stress is not focused on any particular locking shoe which may detrimentally affect the structural integrity of the mechanism as a whole.

More specifically, the locking shoes 56 have a locking portion which comprises a pair of opposed angled surfaces 58 which are separated by a bridge'portion 60 and also includes a rocker portion 62 which is radially inwardly curved as shown. The release mechanism is also provided with a central cam 64 which has a generally circular shape from the end view thereof, and which is inwardly curved laterally along the outer surface 66. When the mechanism is in its armed or locked position, shown in FIG. 3, it is seen that the cam 64 is in contact with the bridge portion 60 of all of the locking shoes 56 and, while in this position, the opposed angled surfaces 580i the locking portion engage the angled surfaces 46 and 48 of the flanges 42 and 44, respectively, and thereby lock the two body sec ons together. Since the presence of the cam 64 prohibits radial movement of the locking shoes while it is in the position shown in FIG. 3, the body sections cannot be separated, since the locking portion of the locking shoes 56 are maintained in firm and immovable contact with the flanges 42 and 44. Stated in other words, and referring to FIG. 3, it is seen that the construction of the mechanism is such that there is virtually solid material vertically along the line of disconnection 18 when the mechanism is in its locked or armed position, with the cam 64 and the bridge portion 60 of the locking shoes 56 substantially filling the area between the side walls, which would prohibit any radially inward movement of the locking shoes 56 that is necessary for separation of the body sections for one another.

To separate the body sections 14 and 16 from one another, it is necessary to have the locking shoes 56 move inwardly out of contact with the angled surfaces 46 and 48 of the flanges 42. and 44. To effect this radially inward movement, the cam 64 with its curved surfaces 66 is moved to the right as shown in FIGS. 3 and 4, by the operation of the piston 40 which is attached to the cam by a shaft 70. When the cam 64 is moved to the right, the curved surfaces 66 come in contact with the rocker portion 62 of the locking shoes and cause the rocker portion 62 of each of the shoes to be moved outwardly toward and into contact with the side walls of the body portion 16. As the rocker portions continue to be moved radially outward in response to further travel to the right of the cam 64, the angled surfaces 58 are moved radially inwardly out of contact with the surfaces 46 and 48 of the flanges to thereby enable release and disconnection of the two body sections 14 and 16 as shown in FIG. 4. A spring 39 may be provided in the connecting the piston to the cam 64, causes the locking shoes to become disengaged from the annular flanges 42 and 44 and permit separation of the body sections 14 and 16.

In keeping with the present invention, the rocker portion 62 of each of the locking shoes 56 also have one or more smaller recesses 72 therein for cooperative engagement with an annular retaining ring 74 which is attached to the side wall of the body section 16 so that the locking shoes are prohibited from sliding to the right when the cam is being moved in the same direction. Thus, the only permitted movement of the locking shoes 56 is the rocking or pivoting movement wherein the rocker portion 62 is moved radially outwardly and the locking portion with the inclined surfaces 58 is moved radially inwardly. In keeping with the present invention, it is contemplated that the area in which the locking shoes and cam 64 are located be sealed from the control area by a wall 76 so that water will not enter the control area 30 after the sections have been separated. In this regard, an o-ring seal (not shown) or other sealing means is preferably provided around the shaft which extends from the compartment 30 so that water cannot enter the compartment between shaft and the wall 76. Moreover, a lubricating fluid, such as oil 'or the like, may be provided within the area housing the locking shoes and cam to further protect the movable components from the corrosive effects of the underwater environment.

Referring to the cross-sectional view shown in FIG. 5, it should be understood that when the locking shoes are in the armed or locked position, they will be in contact with the surface of the outer walls of the body sections 14 and 16 and that during the pivoting movement caused by the cam 64, the left end portion shown in FIGS. 3 and 4 of the locking shoes 56 will be brought toward one another as shown in FIG. 4. Accordingly, it is preferred that the locking shoes be generally triangularly shaped as shown in FIG. 5 so that they can be moved radially inwardly without interfering with one another, particularly in the event a larger number of locking shoes are incorporated as shown for the eight locking shoes illustrated.

In keeping with the present invention and referring to FIG. 6, which illustrates a schematic diagram of the hydraulic system utilized in the mechanism 10, it is preferred that a pair of accumulators 34 be provided to provide increased reliability for the operation of the mechanism, since either accumulator is capable of providing the requisite pressure for driving the piston 40 within the cylinder 38. Thus, each of accumulators 34 has a soienoid valve 36 located within the hydraulic circuit that extends to the piston cylinder and conduits 80 downstream of each of the solenoid valves are combined in a single flow path. It is aiso preferred that a valve 82 be usedto provide a controlled leak within the system so that a leak. in either of the solenoid valves 36 or other valving will not result in a dangerous pressure l t i i fluid will flow to the cylinder 38 without any appreciable pressure loss due to the presence of the controlled leak provided by the valve 82. Stated in other words,

the valve 82 provides a slow acting control pressure bleeding function to prevent gradual build up of dangerous pressures within the conduit, but does not otherwise interfere with a sudden release of the high pressure fluid by the controlled actuation of the mechanism through a command signal generated by the transmitter at a control station or the like.

Thus, a release mechanism for use with large anchor chain or the like has been shown and described which has many desirable attributes and advantages which have been heretofore unavailable. The compact streamlined design, coupled with the isolation of virtually all movable parts from the underwater environment in which the connector is used provides benefits in terms of operational reliability and maintenance.

While the invention is susceptible of various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawings and have been described in detail. it should be understood, however, that it is not intended to limit the invention to the particular form disclosed but, on the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the invention as expressed in the appended claims.

Various features of the invention are set forth in the following claims.

What is claimed is:

1. A remotely actuable release mechanism adapted to interconnect two portions of a chain or the like and to separate said portions from one another while under high tension, said mechanism being adapted for underwater use and comprising:

a body having two mating sections with each of the sections being connected to one of said chain portions so that separation of said body sections separates said chain portions;

movable locking means contained in one of said body sections and movable between a first position locking said body-sections together and a second position wherein said sections can be disconnected;

actuating means in said one body section adapted to move said locking means from said first to said second position in response to receiving a predetermined command signal. 7

2. A mechanism as defined in claim 1 wherein said actuating means including a control section contained within a watertight compartment and having electrical and hydraulic controls, said control section having piston means extending therefrom for moving said locking means from said first to said second position.

3. A release mechanism as defined in claim 1 including means for biasing said locking means in said first position.

4. A release mechanism as defined in claim 1 wherein said actuating means includes means for receiving a predetermined acoustic command signal and moving said locking means in response to receiving said signal.

5. A release mechanism for use with a large chain or the like, and adapted for remote controlled activation, comprising, in combination:

a body comprising two mating sections disconnectable along a line of disconnection, the end of each section having securing means to which link means of the large chain or the like can be attached, each of said sections having a transverse inwardly extending flange adjacent the line of disconnection;

oneor more movable locking shoes having a locking portion bridging said flanges and line of disconnection, said locking shoes havingopposed surfaces for engaging said flanges, said shoes being adapted to prohibit disconnection of said sections when said opposed surfaces thereof are maintained in contact with said flanges;

each of said shoes having an inwardly curved rocker portion at one endthereof adapted to contact the side walls when moved radially outwardly, the outward movement of said rocker portion causing the locking portion to move radially inwardly and disengage the opposed surfaces of said locking portion from said flanges to thereby permit disconnection of said body sections;

cam means located adjacent said locking shoes and normallyholding said locking portion opposed surfaces in contact with said flanges, said cam means being adapted to contact and move said rocker portion radially outwardly and cause said locking portion to move away from said flanges and thereby permit separation of said sections; and,

means for moving said cam means into contact with said rocker portion.

6. A release mechanism as defined in claim 5 wherein said body has an elongated cylindrical shape and said each of said securing means comprises a link portion integrally formed with said body section.

7. A release mechanism as defined in claim 6 wherein said flanges are provided adjacent said line of disconnection and extend around the circumference of said body sections.

8. A release mechanism as defined in claim 6 wherein said curved rocker portion has a surface engageable with the inside surface of said body sidewall and an opposite generally parallel cam surface against which said cam means is adapted to contact.

9. A release mechanism as defined in claim 6 wherein said locking shoes are generally equally spaced from one another, and said cam means is centrally positioned in contact with the locking portion when said mechanism is in its locked configuration.

10. A release mechanism as defined in claim 9 wherein said cam means has a generally circular cross section and a decreasing outside diameter in the direction towards said rocker portion end of said locking shoe.

ll. A release mechanism as defined in claim 5 wherein said two body sections have an annular tongue and cooperative groove on the respective body sections to prevent relative movement therebetween.

12. A release mechanism as defined in claim 5 wherein said cam means has a generally cur ved surface adapted to engage said rocker portion of said locking shoe when said cam means is moved toward said rocker portion.

r i s.

13. A release mechanism as defined in claim wherein said cam moving means includes a shaft coop- Y eratively attached to said cam means.

14. A release mechanism as defined in claim 13 wherein said moving meanscomprises hydraulic piston means seated in a cylinder, said piston means being operativeiy attached to said cam means by said shaft.

15. A release mechanism as defined in claim 5 wherein said locking shoes and cam means arecontained within a generally sealed compartment of said body and said compartment is filled with corrosion protecting liquid.

16. A release mechanism as defined in claim 5 wherein said locking portion of said locking shoes has a recess with the opposite side walls thereof defining said opposed surfaces, said side walls of said body sections being of increased thickness adjacent said disconnec t line defining said transverse inwardly directed flanges.

17. A release mechanism as defined in claim 6 wherein a retaining ring is attached to said cylindrical side wall and cngageable with a recess of each of said locking shoes to prevent sliding movement of said shoes when said cam means is moved into contact therewith.

18. An anchor chain release mechanism adapted for use with means for automatically triggering actuation thereof in response to receiving a command signal activating the same, comprising, in combination:

an elongated body having a generally cylindrical shape with chain segment portions on opposite ends thereof adapted to be attached to a chain link or the like, said body comprising two sections that are releasable and separable relative to one another along a circumferential line of separation, each of said body sections having an inwardly extending annular flange portion immediately adjacent s aid line of separation, said radially directed flanges being integrally formed with the side walls of said body sections;

two or more locking shoes generally equally spaced from one another around the circumference of said cylindrically shaped body, said locking shoes having a recess on theouter side thereof, with opposed surfaces adapted to engage said body section flanges adjacent said line of separation, each of said locking shoes having rocker portions at one end thereof and curved toward the center of said body with the other surface adapted to engage the side walls thereof, said opposed surfaces moving out of contact with said flanges and thereby permit said body sections to separate from one another in response to movement causing the end of said rocker portion to be brought intocontact with said side walls;

cammeans concentrically aligned with said body and contacting said locking shoes to hold said opposed surfaces in contact with said flanges, said cam means being adapted to move axially toward said rocker portions to move the ends thereof into contact with the side walls; and,

means for moving said cam meanstoward said rocker portion in response to receiving an activating command signal. 1=

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION PATENT NO. I 3,905,190

DATED September 16, 1975 INVENTOR(S) Michael D. Pearlman It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 3, line 48 "for" should be -from-.

Column 8, line 16 "other" should be outer.

Signed and Scaled this Attest:

RUTH C. MASON C. IAISIIALL DANN Arresting Officer Commissioner of km: ind Trademarks 

1. A remotely actuable release mechanism adapted to interconnect two portions of a chain or the like and to separate said portions from one another while under high tension, said mechanism being adapted for underwater use and comprising: a body having two mating sections with each of the sections being connected to one of said chain portions so that separation of said body sections separates said chain portions; movable locking means contained in one of said body sections and movable between a first position locking said body sections together and a second position wherein said sections can be disconnected; actuating means in said one body section adapted to move said locking means from said first to said second position in response to receiving a predetermined command signal.
 2. A mechanism as defined in claim 1 wherein said actuating means including a control section contained within a watertight compartment and having electrical and hydraulic controls, said control section having piston means extending therefrom for moving said locking means from said first to said second position.
 3. A release mechanism as defined in claim 1 including means for biasing said locking means in said first position.
 4. A release mechanism as defined in claim 1 wherein said actuating means includes means for receiving a predetermined acoustic command signal and moving said locking means in response to receiving said signal.
 5. A release mechanism for use with a large chain or the like, and adapted for remote controlled activation, comprising, in combination: a body comprising two mating sections disconnectable along a line of disconnection, the end of each section having securing means to which link means of the large chain or the like can be attached, each of said sections having a transverse inwardly extending flange adjacent the line of disconnection; one or more movable locking shoes having a locking portion bridging said flanges and line of disconnection, said locking shoes having opposed surfaces for engaging said flanges, said shoes being adapted to prohibit disconnection of said sections when said opposed surfaces thereof are maintained in contact with said flanges; each of said shoes having an inwardly curved rocker portion at one end thereof adapted to contact the side walls when moved radially outwardly, the outward movement of said rocker portion causing the locking portion to move radially inwardly and disengage the opposed surfaces oF said locking portion from said flanges to thereby permit disconnection of said body sections; cam means located adjacent said locking shoes and normally holding said locking portion opposed surfaces in contact with said flanges, said cam means being adapted to contact and move said rocker portion radially outwardly and cause said locking portion to move away from said flanges and thereby permit separation of said sections; and, means for moving said cam means into contact with said rocker portion.
 6. A release mechanism as defined in claim 5 wherein said body has an elongated cylindrical shape and said each of said securing means comprises a link portion integrally formed with said body section.
 7. A release mechanism as defined in claim 6 wherein said flanges are provided adjacent said line of disconnection and extend around the circumference of said body sections.
 8. A release mechanism as defined in claim 6 wherein said curved rocker portion has a surface engageable with the inside surface of said body sidewall and an opposite generally parallel cam surface against which said cam means is adapted to contact.
 9. A release mechanism as defined in claim 6 wherein said locking shoes are generally equally spaced from one another, and said cam means is centrally positioned in contact with the locking portion when said mechanism is in its locked configuration.
 10. A release mechanism as defined in claim 9 wherein said cam means has a generally circular cross section and a decreasing outside diameter in the direction towards said rocker portion end of said locking shoe.
 11. A release mechanism as defined in claim 5 wherein said two body sections have an annular tongue and cooperative groove on the respective body sections to prevent relative movement therebetween.
 12. A release mechanism as defined in claim 5 wherein said cam means has a generally curved surface adapted to engage said rocker portion of said locking shoe when said cam means is moved toward said rocker portion.
 13. A release mechanism as defined in claim 5 wherein said cam moving means includes a shaft cooperatively attached to said cam means.
 14. A release mechanism as defined in claim 13 wherein said moving means comprises hydraulic piston means seated in a cylinder, said piston means being operatively attached to said cam means by said shaft.
 15. A release mechanism as defined in claim 5 wherein said locking shoes and cam means are contained within a generally sealed compartment of said body and said compartment is filled with corrosion protecting liquid.
 16. A release mechanism as defined in claim 5 wherein said locking portion of said locking shoes has a recess with the opposite side walls thereof defining said opposed surfaces, said side walls of said body sections being of increased thickness adjacent said disconnect line defining said transverse inwardly directed flanges.
 17. A release mechanism as defined in claim 6 wherein a retaining ring is attached to said cylindrical side wall and engageable with a recess of each of said locking shoes to prevent sliding movement of said shoes when said cam means is moved into contact therewith.
 18. An anchor chain release mechanism adapted for use with means for automatically triggering actuation thereof in response to receiving a command signal activating the same, comprising, in combination: an elongated body having a generally cylindrical shape with chain segment portions on opposite ends thereof adapted to be attached to a chain link or the like, said body comprising two sections that are releasable and separable relative to one another along a circumferential line of separation, each of said body sections having an inwardly extending annular flange portion immediately adjacent said line of separation, said radially directed flanges being integrally formed with the side walls of said body sections; two or more locking shoes generally equally spaced from one another around the circumference of said cylindRically shaped body, said locking shoes having a recess on the outer side thereof, with opposed surfaces adapted to engage said body section flanges adjacent said line of separation, each of said locking shoes having rocker portions at one end thereof and curved toward the center of said body with the other surface adapted to engage the side walls thereof, said opposed surfaces moving out of contact with said flanges and thereby permit said body sections to separate from one another in response to movement causing the end of said rocker portion to be brought into contact with said side walls; cam means concentrically aligned with said body and contacting said locking shoes to hold said opposed surfaces in contact with said flanges, said cam means being adapted to move axially toward said rocker portions to move the ends thereof into contact with the side walls; and, means for moving said cam means toward said rocker portion in response to receiving an activating command signal. 